/*
* Forward write_c() on a cheri_fd to the underlying file descriptor.
*/
struct cheri_fd_ret
cheri_fd_write(__capability const void *buf_c, size_t nbytes)
{
struct cheri_fd_ret ret;
__capability struct cheri_fd *cfp;
void *buf;
/* XXXRW: Object-capability user permission check on idc. */
/* XXXRW: Change to check permissions directly and throw exception. */
if (!(cheri_getperm(buf_c) & CHERI_PERM_LOAD)) {
ret.cfr_retval0 = -1;
ret.cfr_retval1 = EPROT;
return (ret);
}
buf = (void *)buf_c;
/* Check that cheri_fd hasn't been revoked. */
cfp = cheri_getidc();
if (cfp->cf_fd == -1) {
ret.cfr_retval0 = -1;
ret.cfr_retval1 = EBADF;
return (ret);
}
/* Forward to operating system. */
ret.cfr_retval0 = write(cfp->cf_fd, buf,
min(nbytes, cheri_getlen(buf_c) - cheri_getoffset(buf_c)));
ret.cfr_retval1 = (ret.cfr_retval0 < 0 ? errno : 0);
return (ret);
}
/*
* Forward fstat() on a cheri_fd to the underlying file descriptor.
*/
struct cheri_fd_ret
cheri_fd_fstat(__capability struct stat *sb_c)
{
struct cheri_fd_ret ret;
__capability struct cheri_fd *cfp;
struct stat *sb;
/* XXXRW: Object-capability user permission check on idc. */
/* XXXRW: Change to check permissions directly and throw exception. */
if (!(cheri_getperm(sb_c) & CHERI_PERM_STORE) ||
!(cheri_getlen(sb_c) >= sizeof(*sb))) {
ret.cfr_retval0 = -1;
ret.cfr_retval1 = EPROT;
return (ret);
}
sb = (void *)sb_c;
/* Check that the cheri_fd hasn't been revoked. */
cfp = cheri_getidc();
if (cfp->cf_fd == -1) {
ret.cfr_retval0 = -1;
ret.cfr_retval1 = EBADF;
return (ret);
}
/* Forward to operating system. */
ret.cfr_retval0 = fstat(cfp->cf_fd, sb);
ret.cfr_retval1 = (ret.cfr_retval0 < 0 ? errno : 0);
return (ret);
}
/*
* Forward lseek() on a cheri_fd to the underlying file descriptor.
*/
struct cheri_fd_ret
cheri_fd_lseek(off_t offset, int whence)
{
struct cheri_fd_ret ret;
__capability struct cheri_fd *cfp;
/* XXXRW: Object-capability user permission check on idc. */
/* Check that the cheri_fd hasn't been revoked. */
cfp = cheri_getidc();
if (cfp->cf_fd == -1) {
ret.cfr_retval0 = -1;
ret.cfr_retval1 = EBADF;
return (ret);
}
/* Forward to operating system. */
ret.cfr_retval0 = lseek(cfp->cf_fd, offset, whence);
ret.cfr_retval1 = (ret.cfr_retval0 < 0 ? errno : 0);
return (ret);
}
__capability struct sandbox *
cheri_getsandbox(void)
{
return (cheri_getidc());
}
